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VLANs
Ingress Filtering is always enabled on the RoamAbout R2. That is, the R2 does NOT
forward data from a VLAN defined on other ports if it is received on a port that is not
configured for that VLAN. In Figure 2-5, should R2(A) be configured incorrectly and
forward VLAN Green data from Switch 2 to R2(E), R2 (E) would not forward the data.
Although other R2(E) ports are configured for VLAN Green, the port receiving the data is
not configured for VLAN Green. It is only configured for VLAN Red. Ingress Filtering
cannot be disabled.
Static and Dynamic VLANs
A static VLAN is created when a user manually configures the ports to be Tagged,
Untagged, or Forbidden. A dynamic VLAN is created when the ports are configured via the
GARP VLAN Registration Protocol (GVRP), which allows network devices to share their
statically configured VLANs. Dynamically configured VLANs are not saved. A reset to the
device causes the device to relearn the dynamic VLANs via GVRP. The RoamAbout R2
supports both statically-configured VLAN settings and GVRP-configured settings.
GVRP only distributes statically configured VLAN information to an adjacent device. In
Figure 2-5, should the Switch 1 port connected to R2(E) be statically configured for VLAN
Gray, GVRP would configure the R2(E) wired port dynamically for VLAN Gray. The
wireless ports would not be configured for VLAN Gray since they are not directly
connected to Switch 1. By default, GVRP is disabled on the R2.